Various systems and methods exist to provide radiation therapy treatment of tumorous tissue with high-energy radiation. While some patient conditions require whole body radiation treatments, many forms of radiation treatment benefit from the ability to accurately control the amount, location and distribution of radiation within a patient's body. Such control often includes applying various levels of radiation to various areas of the tumorous region. For example, in some instances it is desirable to apply a greater dosage of radiation to one portion of a tumorous region than another. As another example, in some instances it is desirable to minimize the dosage of radiation to non tumorous regions where radiation may have deleterious effects. Due to a variety of contributing factors, achieving accurate control of the amount, location and distribution of radiation within the patient's body can be difficult. Among these factors are movement in the patient's body, changes in organ or inter organ structure or composition, and changes in the relative position of a patient's organs.
Prior to a radiation therapy, the patient undergoes an imaging procedure to determine the exact size, shape and location of the tumorous region. In a radiation treatment session, the patient is subjected to radiation from an accelerator that emits a beam of radiation energy collimated and oriented to enter the patient's body from a particular angle. Varying the intensity and the entry angle of the incident radiation beam allows a radiation specialist to generate a radiation dose volume that corresponds to the size, shape, and location of the tumorous region.
Several factors may prevent optimal radiation exposure to the tumorous region and minimal radiation exposure of the healthy tissue regions. For example, minor changes in patient's position from the imaging device to the treatment device may radically alter the position of the tumorous region or organ. In existing procedures, the patient is generally placed on a first patient support when the imaging device is used to obtain images of the patient. After the imaging session, the patient is then moved to a second patient support where the patient can be treated in a treatment session. As a result of moving the patient to different supports, the position and/or the shape of the target tissue within the patient may change. As such, it may be desirable to provide a patient support system that is capable of supporting a patient during an imaging procedure and/or treatment session.
Another problem associated with existing patient support systems is that they have limited range of movements and limited degrees of freedom. For example, in certain procedures, it may be desirable to rotate a patient support about its longitudinal axis to thereby tilt the patient support. However, existing patient support systems may not be configured to allow rotation of the patient support about its longitudinal axis.